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据IPCC报告,全球尺度温度水平在2017年相比工业革命前上升了约1 ℃,若不采取必要措施,预计2030—2052年期间将增温1.5 ℃[1]。全球变暖主要与大气中CH4、N2O、CO2等温室气体的浓度升高有关。自工业革命以来,大气中CH4、N2O、CO2的浓度分别增加了150%、40%、20%。CH4和N2O作为2种重要的温室气体,百年尺度的全球增温潜势(GWP)是CO2的25倍和265倍[2],农田土壤作为CH4和N2O的主要人为排放源,分别占据全球人为CH4和N2O排放量的50%和60%[3-4],其产生主要受气候类型、施肥模式、作物类型和种植制度等多种因素影响[5]。增加土壤碳固定是一种减少温室气体排放潜力很大的策略[6]。
海南热带地区雨热同期,稻田干湿交替现象频发而易于N2O产生,随之CH4排放可能受到影响而降低[7]。然而,海南全年高温、降雨充沛的条件有利于土壤和作物碳代谢,可能增加CH4排放[8]。田伟等[9]对琼北晚稻田的原位监测发现热带地区稻田CH4、N2O排放分别达到50.6~175.7、0.44~3.40 kg·hm−2;WELLER等[10]在菲律宾洛斯巴尼奥斯国际试验站对水稻-水稻、水稻-玉米轮作长期监测发现,CH4、N2O排放分别达到46.5~288.2、1.5~8.0 kg·hm−2;石生伟等[11]研究表明,我国非热带地区典型水稻种植区相同灌溉模式下CH4、N2O排放分别为84~144 、0.6~2.07 kg·hm−2 ,表现出热带地区稻田高CH4和N2O排放特征。因此,需迫切探求我国热带地区CH4和N2O减排的有效措施。生物炭作为一种新型土壤改良剂,因其具有丰富多孔结构、比表面积大、对矿态氮吸附能力强及提升土壤pH等特性而被广泛应用于温室气体减排研究[12]。因此,农田生态系统添加生物炭被认为是最具潜力的减排措施之一,减排潜力可达0.7 Gt C-eq·a[13]。大量研究表明,生物炭能通过改善土壤理化性质而减少温室气体排放[8, 14-15],但也有研究表明,生物炭会显著增加温室气体排放[16],或影响不显著[17]。作物秸秆还田被认为是补充土壤养分和降低温室气体排放的措施[18-19];张杏雨等[20]综述中表明,秸秆还田能降低、或者增加温室气体排放。许多研究结果表明,单独施入秸秆或生物炭,对CH4和N2O排放的影响成相反趋势[18, 21],如秸秆在稻田中施用易促进CH4排放[22],而生物炭能提高土壤pH和土壤孔隙度,有利于CH4氧化,则会减少CH4排放[15]。生物炭大多呈碱性,施入土壤可能会促进NO3−-N产生导致硝态氮含量增加而不利于氮素的保持;有研究表明,秸秆添加能有效固定土壤中矿态氮含量,从而减少氮素损失和N2O排放[22],但也有研究表明,在高含水量或大量添加秸秆条件下,秸秆好氧分解会导致氧气含量降低,这在高硝态氮背景下利于促进反硝化过程造成损失而非促进硝态氮固定[23],生物炭作为一种能提高土壤孔隙度的改良剂,施用生物炭有利于无机氮的固定而抑制反硝化过程[24]。因此,秸秆和生物炭联用或许能同时达到增产、减少氮素损失和温室气体排放的目的。以往研究大多集中于单施秸秆或者生物炭[14, 18],以及在旱地中联合施用[23, 25-26],少有生物炭和秸秆联用在水稻田中对温室气体排放影响的研究。在生物炭施用情况下秸秆还田会对稻田温室气体排放带来何种影响尚不明确。生物炭施用情况下若能进行秸秆还田,对生物质资源循环利用具有重要意义。基于此,本研究以稻-菜轮作体系土壤为基础,采用盆栽培养的方法,设置常规对照、添加生物炭、添加水稻秸秆以及生物炭与秸秆联用4个处理,监测整个水稻种植季CH4和N2O排放。并通过测定水稻收获后土壤微生物量碳、微生物量氮(MBC/MBN)、作物产量和估算GWP,综合探究生物炭、秸秆、生物炭与秸秆联用对温室气体排放和水稻产量的影响,以期为田间生产提供指导。
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供试土壤取自海南省澄迈县西岸村(19°55′ N,109°57′ E)稻菜轮作田块的土壤,在水稻季结束后采集。该区域属典型热带季风气候,年均温、降雨量分别为23. 80 ℃、1 786. 10 mm。试验土壤为滨海沉积物母质发育的水稻土,质地为砂壤土。土壤经风干后去除石砾和植物根系并过2 mm筛,土壤背景理化值分别为:土壤pH 5.90,有机碳含量15.66 g·kg−1,碱解氮含量116.93 mg·kg−1,速效磷含量167.50 mg·kg−1,速效钾含量74.94 mg·kg−1,砂粒61.70%,粉粒20.5%,黏粒17.80%。
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盆栽试验选用水稻品种为‘特优808’,育苗20 d进行移栽。试验共设计4个处理,每个处理设置4个平行并按随机区组排列,分别为常规施肥处理(CK);常规施肥处理基础上添加40 t·hm−2生物炭处理(B); 常规施肥处理基础上添加3 t·hm−2水稻秸秆处理 (C); 常规施肥处理基础上添加40 t·hm−2椰糠生物炭+3 t·hm−2水稻秸秆处理(B+C)。水分管理按照淹水-晒田1周-复水-收获前保持湿润进行。于2020−05−19,按各处理将准备好的土壤、生物炭和秸秆混匀装入盆栽装置,每盆装土5 kg,并加水至土壤孔隙含水量(WFPS)60%进行活化。5月26日活化完成后淹水5 cm并将秧苗移栽入盆中,隔天第1次采集气体。6月5日进行第1次施肥,分别施尿素0.49 g、过磷酸钙0.85 g、氯化钾0.30 g;6月30日施第2次肥,分别施尿素0.33 g、过磷酸钙0.56 g、氯化钾0.20 g,各处理施肥方案一致。试验期间各项农事管理措施一致。
供试生物炭由椰糠在600 ℃下厌氧热解制成,pH 9.7、全碳含量为676.78 g·kg−1、全氮含量为5.03 g·kg−1、碳氮比为134.49、比表面积为5.84 m2·g−1;水稻秸秆经烘箱烘干粉碎机粉碎过2 mm筛备用。
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气体样品采集采用密闭静态暗箱观测法,盆栽装置外围安装采气底座(53 cm×53 cm),边缘设置宽2.5 cm的蓄水槽用于密封。用白色PVC板制作采气箱(50 cm×50 cm×100 cm)用于气体样品采集。箱体外部包裹泡沫塑料保温层,以防箱内升温过快、箱顶侧边设有温度计连接口和带三通阀的采气口。采气前向底座凹槽内适量灌水以形成密闭环境,后将采样箱扣于底座凹槽上计时采气。采气时先用100 mL针管反复抽动几次使箱体内空气混匀,后于0、10、20、30 min抽取60 mL气体注入提前抽真空的20 mL顶空瓶(Nichiden-rika Glass Co. Ltd.)。采气时间为上午 08: 00 —11: 00,常规采气频率为1周1次,施肥后加密采样1次。所采气样带回实验室用气相色谱仪(岛津 GC-2014)进行分析,N2O检测器为电子捕获检测器(ECD),载气为氩甲烷;CH4检测器为氢焰电离检测器(FID),载气为高纯氮,检测器温度 300 ℃。标准气体由中国计量科学研究院提供。
采气当天用便携式Eh计(Bante 220)测定土壤Eh和土壤温度;土壤微生物量碳(MBC)和微生物量氮(MBN)含量采用氯仿熏蒸—K2SO4 提取法进行测定[27];土壤pH采用pH计(雷磁 PHS-3C)进行测定;土壤NH4+-N和NO3−-N含量,用2 mol·L KCl浸提—连续流动分析仪(Proxima 1022/1/1,爱利安斯科学仪器公司,法国)进行测定,土壤其他基本性质测定方法参考鲍士旦《土壤农化分析》[28]。
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CH4和N2O排放通量计算公式:
$$ F=\rho \times \frac{\Delta c}{\Delta t} \times \frac{273.15}{273.15+T} \times h ,$$ 式中,F为气体排放通量,
${F_{{{\rm{N}}_2}{\rm{O}}}} $ 单位为μg·(m2·h)−1 ,${F_{{\rm{C}}{{\rm{H}}_{\rm{4}}}}} $ 单位为mg·(m2·h)−1;ρ为标准状态下CH4-C和N2O-N的密度/(kg·m−3);h为采样箱高度/m;Δc/Δt为采样过程中箱内气体摩尔分数变化速率;T 为采样时箱内平均温度/℃。累积排放量(ƒ,kg·hm−2)计算公式如下:
$$ f = \sum\nolimits_{i=1}^{n}\left(F_{i} \times 24\right)+\sum\nolimits_{i=1}^{\mathrm{n}} \left[\frac{F_{i}+F_{i+1}}{2} \times \left(t_{i+1}-t_{i}-1\right) \times 24\right] , $$ 式中,n和i为采样次数,t为采样天数/d。
100 a尺度的农田土壤直接排放的N2O、CH4增温潜势(GWPGHGS,CO2-eq,kg·hm−2 ) 计算公式[2]:
$$ \mathrm{GWP}_{\mathrm{GHGS}}=f_{\mathrm{N}_{2} \mathrm{O}} \times 265+f_{\mathrm{CH}_{4}} \times 25, $$ 使用SPSS 23. 0 进行皮尔森相关分析和单因素方差分析和 Origin2018 绘图。处理间差异采用Duncan多重比较法;P<0.05为显著水平。
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种植前期,各处理土壤Eh均维持在较低水平且低于−150 mV,其中B+C处理明显低于其他处理;移栽1月进行晒田后,土壤Eh逐渐升高至30 mV左右;复水后Eh逐渐下降并总体维持在−120 mV上下波动直至收获。各处理Eh变化趋势一致(图1-a):CK、B、C和B+C 4个处理Eh均值分别为−114.38 、−109.78 、−117.06 和−121.86 mV。5 cm土壤温度各处理温差在2 ℃内且趋势一致(图1-b)。
土壤NH4+-N和NO3−-N含量变化如图2所示。各处理土壤NH4+-N在第1次施肥后升高,C处理峰值最低、B和B+C处理峰值高于CK处理,后随时间延续下降,晒田期后B、C和B+C 处理NH4+-N含量均明显低于CK处理(图2-a)。土壤NO3−-N含量在2次施肥后各处理响应不同,第1次施肥后B+C处理NO3−-N含量下降、其他处理升高,但B、C和B+C处理NO3−-N含量逐渐低于CK处理;晒田期后B和C处理NO3−-N含量均明显低于CK处理且C处理NO3−-N 含量一直维持在最低水平,而B+C处理NO3−-N 含量明显高于CK处理并逐渐下降到最低水平(图2-b)
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观测期内各处理CH4通量为0.1~25.0 mg·m−2·h−1(图3-a)。第1次施肥后,相比其他处理,B+C处理对CH4排放通量响应较快,一直处于上升趋势直至晒田期前夕出现峰值;CK、B和C处理第1次施肥后对CH4排放通量响应较慢,并且峰值较小,添加生物炭处理峰值最低;晒田管理明显抑制CH4排放通量,各处理在晒田期CH4排放通量直线下降,晒田期结束复水进行第2次施肥后各处理出现第2个峰值,B+C处理CH4排放通量最高;大量CH4排放出现在水稻种植孕穗期至收获期,各处理CH4排放通量呈上升趋势于收获前回降。CK、B、C和B+C 4个处理CH4累计排放分别为106.16、66.29、121.69和129.52 kg·hm−2;相比CK处理,B处理显著降低CH4排放37.56%、C和B+C处理分别显著增加CH4排放14.63%和22.01%(P<0.05)(图4-a)。
观测期内各处理N2O排放通量在49.0~256.3 μg·m−2·h−1之间,晒田期各处理排放通量升高,在施肥后出现峰值、且第2次峰值较第1个高(图3-b)。CK处理的2次排放峰值均最高且其N2O排放通量在整个种植期维持在较高水平。CK、B、C和B+C 4个处理N2O累计排放分别为2.61、2.05、2.04和2.22 kg·hm−2。相比CK处理,B、C和B+C处理分别显著减少了N2O累计排放21.43%、21.89%和14.77%,B、C处理N2O累计排放显著低于B+C处理(P<0.05)(图4-b)。
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收获后,CK、B、C和B+C 4个处理单株水稻产量分别为57.87、60.90、62.94和47.23 g/株;B和C处理分别显著增加单株水稻产量5.22%、8.76%,B+C处理显著降低单株水稻产量18.39%(图5-a)(P<0.05)。
CK、B、C和B+C 4个处理GWP分别为3.35、2.18、3.58和3.77 t CO2-eq ha−2;B处理显著降低GWP 34.74%、而C和B+C处理分别显著增加GWP 7.08%和12.69%(图5b)(P<0.05)。
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收获后,CK、B、C和B+C 4个处理单株水稻生物量分别为140.57、156.38、163.80和141.77 g·株−1;B和C处理分别显著增加水稻生物量11.25%和16.53%(P<0.05),B+C处理增加水稻生物量0.85%但不显著(图6)。
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水稻收割后对土壤微生物量碳、微生物量氮进行了测定。相比CK处理,B处理显著提高土壤微生物量碳(MBC)含量10.52%、C处理显著降低土壤微生物量碳(MBC)含量7.18%(P<0.05),而B+C处理土壤微生物量碳(MBC)含量提高5.32%但不显著(图7-a)。与CK处理相比,B处理土壤微生物量氮含量与CK相当,而C和B+C处理分别显著降低土壤微生物量氮(MBN)含量12.89%和6.26%(P<0.05)(图7-b)。
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相关性分析结果表明,各处理N2O排放通量与Eh呈极显著正相关(P<0.01)、而与5 cm土温相关性不显著,C处理N2O排放通量与NO3−-N显著相关、B+C处理N2O排放通量与NO3−-N极显著相关;CK、B和C处理CH4排放通量与5 cm土温呈极显著负相关,而B+C处理与5 cm土温相关性不显著,除C处理以外,各处理CH4排放通量与NO3−-N极显著负相关(表1)。
表 1 不同处理CH4和N2O排放通量与Eh、5 cm土温的相关性
处理 CH4排放通量 N2O排放通量 Eh 5 cm土温 NH4+-N NO3−-N Eh 5 cm土温 NH4+-N NO3−-N CK −0.025 −0.540** −0.071 −0.519** 0.566** −0.094 −0.165 0.286 B 0.056 −0.453** −0.337 −0.624** 0.385** −0.067 0.275 0.309 C −0.026 −0.540** −0.359 −0.286 0.466** −0.242 0.502* 0.567* B+C −0.247 −0.160 −0.158 −0.690** 0.590** −0.164 −0.147 0.541** 注:“*” 表示 0.05 水平显著,“**”表示 0.01 水平显著。
Effect of biochar and its combined application with straw on CH4 and N2O in paddy field soils in tropical China
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摘要: 为了研究添加生物炭、秸秆、生物炭与秸秆联用对热带地区稻田温室气体排放的影响,通过盆栽培养试验,设常规施肥(CK)、常规施肥配施 40 t·hm−2 椰糠生物炭(B)、常规施肥配施3 t·hm−2水稻秸秆(C)、常规施肥配施 40 t·hm−2 椰糠生物炭加3 t·hm−2水稻秸秆(B+C)4个处理,采用静态箱-气相色谱法监测整个水稻种植季CH4和N2O排放,估算全球增温潜势(GWP)并测定收获后作物产量。结果表明,相比CK处理, B、C和B+C处理的N2O累计排放量分别降低21.43%、21.89%和14.77%;B处理的CH4累计排放量降低38.21%,而C和B+C处理的CH4累计排放量分别增加14.63%和19.85%;C和B+C处理显著增加GWP,而B处理显著降低GWP;单独添加生物炭减排效果最佳。与CK相比,B、C处理的单株水稻产量分别增加5.22%、8.76%,而B+C处理的单株水稻产量降低18.39% (P<0.05)。因此,在我国热带地区稻田,单独施用40 t·hm−2生物炭,可以实现温室气体减排和增产,值得在田间推广应用。Abstract: Effective measures of greenhouse gas emission mitigation in paddy field in tropical China are still unclear. In order to explore the effect of biochar, straw amendment and the mixture of biochar and straw on greenhouse gas emission in paddy fields in tropical China, a pot experiment was conducted, and four treatments were arranged, including conventional fertilizer application as control (CK), conventional fertilizer application plus 40 t·hm−2 of biochar (B), conventional fertilizer application plus 3 t·hm−2 of rice straw (C), conventional fertilizer application plus 40 t·hm−2 of biochar + 3 t·hm−2 of rice straw (B+C). Static chamber-gas chromatography was used to monitor CH4 and N2O emissions for estimation of global warming potential (GWP), and the crop yield was measured after harvest. The results showed that compared with CK Treatments B, C and B+C significantly reduced the cumulative N2O emissions by 21.43%, 21.89%, and 14.77%, respectively, but only Treatment B significantly reduced the cumulative emission of CH4 by 38.21%, while Treatments C and B+C significantly increased the cumulative emission of CH4 by 14.63% and 19.85%, respectively. Meanwhile, Treatments C and B+C significantly increased GWP, while Treatment B significantly decreased GWP (P < 0.05), which indicated that Treatment B had better greenhouse gas emission mitigation effect as compared to the other treatments. Treatments B and C significantly increased rice yield per plant by 5.22% and 8.76%, respectively, while Treatment B+C significantly decreased rice yield per plant by 18.39%. Thus, application of 40 t·hm−2 of biochar in the paddy fields in tropical China is recommended to achieve greenhouse gas emission reduction and yield increase.
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Key words:
- biochar /
- greenhouse gas /
- tropical region /
- straw returning
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表 1 不同处理CH4和N2O排放通量与Eh、5 cm土温的相关性
处理 CH4排放通量 N2O排放通量 Eh 5 cm土温 NH4+-N NO3−-N Eh 5 cm土温 NH4+-N NO3−-N CK −0.025 −0.540** −0.071 −0.519** 0.566** −0.094 −0.165 0.286 B 0.056 −0.453** −0.337 −0.624** 0.385** −0.067 0.275 0.309 C −0.026 −0.540** −0.359 −0.286 0.466** −0.242 0.502* 0.567* B+C −0.247 −0.160 −0.158 −0.690** 0.590** −0.164 −0.147 0.541** 注:“*” 表示 0.05 水平显著,“**”表示 0.01 水平显著。 -
[1] IPCC. Global Warming of 1.5 ℃: An IPCC Special Report on the impacts of global warming of 1.5℃ above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty [M]. Cambridge: Cambridge University Press, 2018. [2] IPCC. Climate Change 2014: Mitigation of climatechange. Contribution of working group III to the fifth assessment report of the intergovernmental panel on climate change [M]. Cambridge: Cambridge University Press, 2014. [3] ZHOU M, WANG X, WANG Y, et al. A three-year experiment of annual methane and nitrous oxide emissions from the subtropical permanently flooded rice paddy fields of China: emission factor, temperature sensitivity and fertilizer nitrogen effect [J]. Agricultural and Forest Meteorology, 2018, 250: 299 − 307. [4] ASHIQ W, NADEEM M, ALI W, et al. Biochar amendment mitigates greenhouse gases emission and global warming potential in dairy manure based silage corn in boreal climate [J]. Environmental Pollution, 2020, 265: 114869. doi: 10.1016/j.envpol.2020.114869 [5] 胡玉麟, 汤水荣, 陶凯, 等. 优化施肥模式对我国热带地区水稻-豇豆轮作系统 N2O 和 CH4排放的影响[J]. 环境科学, 2019, 40(11): 5182 − 5190. [6] SMITH P, MARTINO D, CAI Z, et al. Greenhouse Gas mitigation in agriculture [J]. Philosophical Transactions:Biological Sciences, 2008, 363(1492): 789 − 813. doi: 10.1098/rstb.2007.2184 [7] XING G, ZHAO X, XIONG Z Q, et al. Nitrous oxide emission from paddy fields in China [J]. Acta Ecologica Sinica, 2009, 29(1): 45 − 50. doi: 10.1016/j.chnaes.2009.04.006 [8] 王紫君, 王鸿浩, 李金秋, 等. 椰糠生物炭对热区双季稻田N2O和CH4排放的影响[J]. 环境科学, 2021, 42(8): 3931 − 3942. [9] 田伟, 伍延正, 孟磊, 等. 不同施肥模式对热区晚稻水田CH4 和N2O排放的影响[J]. 环境科学, 2019, 40(5): 2426 − 2434. [10] WELLER S, JANZ B, JORG L, et al. Greenhouse gas emissions and global warming potential of traditional and diversified tropical rice rotation systems [J]. Global Change Biology, 2016, 22(1): 432 − 448. doi: 10.1111/gcb.13099 [11] 石生伟, 李玉娥, 刘运通, 等. 中国稻田CH4和N2O排放及减排整合分析[J]. 中国农业科学, 2010, 43(14): 2923 − 2936. doi: 10.3864/j.issn.0578-1752.2010.14.011 [12] RIBAS A, MATTANA S, LLURBA R, et al. Biochar application and summer temperatures reduce N2O and enhance CH4 emissions in a Mediterranean agroecosystem: Role of biologically-induced anoxic microsites [J]. Science of the Total Environment, 2019, 685: 1075 − 1086. doi: 10.1016/j.scitotenv.2019.06.277 [13] SMITH P. Soil carbon sequestration and biochar as negative emission technologies [J]. Global Chang Biology, 2016, 22(3): 1315 − 1324. doi: 10.1111/gcb.13178 [14] 汪勇, 吕茹洁, 黎星, 等. 生物炭与氮肥施用对双季稻田温室气体排放的影响[J]. 中国稻米, 2021, 27(1): 20 − 26. [15] HUANG Y, WANG C, LIN C, et al. Methane and nitrous oxide flux after biochar application in subtropical acidic paddy soils under tobacco-rice rotation [J]. Scientific RepoRtS, 2019, 9(1): 17277. doi: 10.1038/s41598-019-53044-1 [16] LIU X, REN J, ZHANG Q, et al. Long-term effects of biochar addition and straw return on N2O fluxes and the related functional gene abundances under wheat-maize rotation system in the North China Plain [J]. Applied Soil Ecology, 2019, 135: 44 − 55. doi: 10.1016/j.apsoil.2018.11.006 [17] ZHANG A F, CUI L Q, PAN G X, et al. Effect of biochar amendment on yield and methane and nitrous oxide emissions from a rice paddy from Tai Lake plain, China [J]. Agriculture, Ecosystems and Environment, 2010, 139(4): 469 − 475. doi: 10.1016/j.agee.2010.09.003 [18] SHEN J L, TANG H, LIU J Y, et al. Contrasting effects of straw and straw-derived biochar amendments on greenhouse gas emissions within double rice cropping systems [J]. Agriculture, Ecosystems and Environment, 2014, 188: 264 − 274. doi: 10.1016/j.agee.2014.03.002 [19] 桑琳. 增温及秸秆施用对农田土壤呼吸及酶活性的影响 [D]. 南京: 南京信息工程大学, 2017. [20] 张杏雨, 李思宇, 余锋, 等. 作物秸秆还田对稻田温室气体排放效应的研究进展[J]. 杂交水稻, 2021, 36(5): 1 − 7. [21] ZHANG A, CHENG G, HUSSAIN Q, et al. Contrasting effects of straw and straw–derived biochar application on net global warming potential in the Loess Plateau of China [J]. Field Crops Research, 2017, 205: 45 − 54. doi: 10.1016/j.fcr.2017.02.006 [22] WANG J, CHEN Z, XU C, et al. Organic amendment enhanced microbial nitrate immobilization with negligible denitrification nitrogen loss in an upland soil [J]. Environmental Pollution, 2021, 288: 117721. doi: 10.1016/j.envpol.2021.117721 [23] DUAN M, WU F, JIA Z, et al. Wheat straw and its biochar differently affect soil properties and field-based greenhouse gas emission in a Chernozemic soil [J]. Biology and Fertility of Soils, 2020, 56(7): 1023 − 1036. doi: 10.1007/s00374-020-01479-4 [24] LIU X, MAO P, LI L, et al. Impact of biochar application on yield-scaled greenhouse gas intensity: A meta-analysis [J]. Science of the Total Environment, 2019, 656: 969 − 976. doi: 10.1016/j.scitotenv.2018.11.396 [25] 唐占明, 刘杏认, 张晴雯, 等. 对比研究生物炭和秸秆对麦玉轮作系统N2O排放的影响[J]. 环境科学, 2021, 42(3): 1569 − 1580. [26] WU Q, LIAN R, BAI M, et al. Biochar co-application mitigated the stimulation of organic amendments on soil respiration by decreasing microbial activities in an infertile soil [J]. Biology and Fertility of Soils, 2021, 57(6): 793 − 807. doi: 10.1007/s00374-021-01574-0 [27] 吴金水, 林启美. 土壤微生物生物量测定方法及其应用 [M]. 北京: 气象出版社, 2006. [28] 鲍士旦. 土壤农化分析 [M]. 北京: 中国农业出版社, 2000. [29] FENG Y Z, XU Y P, YU Y C, et al. Mechanisms of biochar decreasing methane emission from Chinese paddy soils [J]. Soil Biology and Biochemistry, 2011, 46: 80 − 88. [30] STEINBEISS S, GLEIXNER G, ANTONIETTI M. Effect of biochar amendment on soil carbon balance and soil microbial activity [J]. Soil Biology and Biochemistry, 2009, 41(6): 1301 − 1310. doi: 10.1016/j.soilbio.2009.03.016 [31] WANG W, CHEN C, WU X, et al. Effects of reduced chemical fertilizer combined with straw retention on greenhouse gas budget and crop production in double rice fields [J]. Biology and Fertility of Soils, 2018, 55(1): 89 − 96. [32] HUANG S, SUN Y N, YU X C, et al. Interactive effects of temperature and moisture on CO2 and CH4 production in a paddy soil under long-term different fertilization regimes [J]. Biology and Fertility of Soils, 2016, 52(3): 285 − 294. doi: 10.1007/s00374-015-1075-3 [33] WEI L, GE T, ZHU Z, et al. Paddy soils have a much higher microbial biomass content than upland soils: A review of the origin, mechanisms, and drivers [J]. Agriculture, Ecosystems and Environment, 2022, 326: 107798. doi: 10.1016/j.agee.2021.107798 [34] CHEN H H, LI X C, HU F, et al. Soil nitrous oxide emissions following crop residue addition: a meta-analysis [J]. Global change biology, 2013, 19(10): 2956 − 2964. doi: 10.1111/gcb.12274 [35] WANG H, YU L F, ZHANG Z H, et al. Molecular mechanisms of water table lowering and nitrogen deposition in affecting greenhouse gas emissions from a Tibetan alpine wetland [J]. Global Change Biology, 2017, 23(2): 815 − 829. doi: 10.1111/gcb.13467 [36] HU A, LU Y. The differential effects of ammonium and nitrate on methanotrophs in rice field soil [J]. Soil Biology and Biochemistry, 2015, 85: 31 − 38. doi: 10.1016/j.soilbio.2015.02.033 [37] 王鸿浩, 谭梦怡, 王紫君, 等. 不同水分管理条件下添加生物炭对琼北地区水稻土N2O排放的影响[J]. 环境科学, 2021, 65(2): 3943 − 3952. [38] 曹文超. 农田土壤N2O排放的关键过程及影响因素[J]. 植物营养与肥料学报, 2019, 25(10): 1781 − 1798. doi: 10.11674/zwyf.18441 [39] 程谊, 张金波, 蔡祖聪. 气候-土壤-作物之间氮形态契合在氮肥管理中的关键作用[J]. 土壤学报, 2019, 56(3): 507 − 515. doi: 10.11766/trxb201812030523 [40] NOVAK J M, BUSSCHER W J, WATTS D W, et al. Short-term CO2 mineralization after additions of biochar and switchgrass to a Typic Kandiudult [J]. Geoderma, 2010, 154(3-4): 281 − 288. doi: 10.1016/j.geoderma.2009.10.014 [41] WU Y, LI Y, WANG H, et al. Response of N2O emissions to biochar amendment on a tea field soil in subtropical central China: A three-year field experiment [J]. Agriculture, Ecosystems and Environment, 2021, 318: 107473. doi: 10.1016/j.agee.2021.107473 [42] LIU J, JIANG B S, SHEN J L, et al. Contrasting effects of straw and straw-derived biochar applications on soil carbon accumulation and nitrogen use efficiency in double-rice cropping systems [J]. Agriculture, Ecosystems and Environment, 2021, 311: 107286. doi: 10.1016/j.agee.2020.107286 [43] 房秋娜. 外源碳氮和秸秆还田对土壤酶活性和碳组分及水稻产量的影响 [D]. 哈尔滨: 东北农业大学, 2021.